Coreless paper roll manufacturing method

ABSTRACT

A manufacturing method includes: a first step for winding up paper to form paper roll; a second step for inserting an insertion section, which ejects an adhesive, into a center hole of the paper roll; a third step for causing the adhesive to adhere to a predetermined position of the center hole; and a fourth step for performing a heating and drying process on an area to which the adhesive is adhered to harden opposite ends of the center hole. The third step includes causing the adhesive to adhere to near opposite extending ends of the center hole. The adhesive has adhesive strength to an extent that the paper wound up into the roll shape is peelable when the paper roll is to be used. The fourth step includes drying the adhesive adhered to the center hole before the adhesive spreads from the predetermined position of the center hole.

TECHNICAL FIELD

The present invention relates to a method for manufacturing coreless paper roll wound up without being provided with a core, such as paperboard.

BACKGROUND ART

For example, when a thin paper material (paper) is to be wound up into a roll, as in a toilet paper roll, the manufacturing process involves preparing a substantially tubular core formed of, for example, paperboard, and winding the paper around this core. When the toilet paper roll is completely used up, the remaining core becomes waste. For this reason, there are coreless toilet paper rolls that are formed without using cores.

For example, the manufacturing process for a coreless toilet paper roll involves spraying, for example, an adhesive with low adhesive strength onto the leading edge of the paper, wrapping the leading edge of the paper around a winding shaft, and sequentially winding up the paper into a roll (e.g. see Patent Literature 1). In detail, when a coreless toilet paper roll is to be manufactured, the leading edge of the paper is wrapped around the winding shaft and, while the paper is being wound up by five to six turns from the leading edge, the adhesive or the like is sprayed onto this section so that this section is adhered to form a tubular shape. Furthermore, for example, when the paper is being wound up as described above, the winding shaft is heated so that the sprayed an dhesive or the like is dried.

There is also a coreless-toilet-paper-roll manufacturing apparatus in which a shaft of a riding roller that comes into contact with the outer periphery of wound paper when the paper is wound around a winding shaft is provided with holes from which an adhesive exudes (e.g. see Patent Literature 2).

This apparatus performs a manufacturing process including a paper winding step that involves suctioning the adhesive into the shaft of the riding roller, applying the adhesive to paper nipped between the riding roller and the winding shaft by causing the adhesive to exude to the surface of the shaft, and winding up this paper around the winding shaft into a roll shape. In detail, with regard to the riding roller, a roller section formed of a thick-walled cylindrical sponge is fitted around the shaft provided with the holes, as described above. Small capillary tubes are formed between the inner wall and the outer wall of the roller section, and the adhesive exuding from the surface of the shaft reaches the surface of the roller section via the capillary tubes. The adhesive exuding to the surface of the roller section is applied to the paper nipped between the winding shaft and the riding roller, so that the center of the toilet paper roll is hardened.

CITATION LIST Patent Literature

PTL 1: Japanese Unexamined Patent Application Publication No. 6-199452

PTL 2: Japanese Unexamined Patent Application Publication No. 9-216755

SUMMARY OF INVENTION Technical Problem

Because the coreless paper roll in the related art is manufactured in the above-described manner, the leading wound section of the paper is hardened to become a tubular shape. Thus, when the time approaches for using up the paper roll, for example, it becomes difficult to remove the paper roll from the holder holding the paper roll, thus making it difficult to completely use up the paper roll even if it is of a coreless type. This is problematic in that the hardened section at the center of the roll may be left unused.

The present invention has been made to solve the aforementioned problem, and an object thereof is to provide a coreless paper roll manufacturing method for manufacturing roll-shaped wound paper that can be used up to its last edge.

Solution to Problem

A coreless paper roll manufacturing method according to this invention includes a first step for winding up paper to form paper roll having a roll shape; a second step for inserting an insertion section, which ejects an adhesive, into a center hole of the paper roll; a third step for causing the adhesive to adhere to a predetermined position of the center hole; and a fourth step for performing a heating and drying process on an area to which the adhesive is adhered so as to harden opposite ends of the center hole. The third step includes causing the adhesive to adhere to near opposite extending ends of the center hole. The adhesive has adhesive strength to an extent that the paper wound up into the roll shape is peelable when the paper roll is to be used. The fourth step includes drying the adhesive adhered to the center hole before the adhesive spreads from the predetermined position of the center hole.

Furthermore, the second step includes inserting the insertion section toward a middle of the center hole from the opposite extending ends of the center hole and increasing a hole diameter at the opposite ends of the center hole to a predetermined size, and the third step includes causing the adhesive to adhere to areas of the center hole with the increased hole diameter.

Moreover, the third step includes decreasing an adhered amount of the adhesive toward a middle of the center hole from the opposite extending ends of the center hole, and the fourth step includes performing heating and drying such that the opposite ends of the center hole are maximally hardened.

Advantageous Effects of Invention

According to the present invention, paper roll can be prevented from easily losing its shape in its packaged state when being shipped and transported or the like, and can be completely used up without leaving behind a core or the like when being used.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a perspective view illustrating coreless toilet paper manufactured by using a coreless paper roll manufacturing method according to a first embodiment of the present invention.

FIG. 2 is an explanatory view illustrating a step for manufacturing the coreless paper roll illustrated in FIG. 1.

FIG. 3 is an explanatory view illustrates a step for manufacturing the coreless paper roll illustrated in FIG. 1.

FIG. 4 is an explanatory view illustrating a step for manufacturing coreless paper roll by using a coreless paper roll manufacturing method according to a second embodiment of the present invention.

FIG. 5 is an explanatory view illustrating a step for manufacturing the coreless paper roll by using the coreless paper roll manufacturing method according to the second embodiment.

DESCRIPTION OF EMBODIMENTS

Embodiments of the present invention will be described below.

First Embodiment

FIG. 1 is a perspective view illustrating coreless toilet paper manufactured by using a coreless paper roll manufacturing method according to a first embodiment of the present invention. Paper roll 1 illustrated is coreless toilet paper not provided with a core, such as paperboard, and manufactured by winding up paper 2 having a center hole 3 as a through hole connecting opposite sides of the roll. The center hole 3 has an inner diameter similar to that of a common paperboard core.

Hole ends 3 a and 3 b (openings) serving as opposite ends of the center hole 3 are sprayed with an adhesive or the like, which will be described later, so as to be adequately hardened. The hole ends 3 a and 3 b are hardened to an extent such that, when the paper 2 is pulled from the paper roll 1, the paper 2 that is layered by being wound up is peeled without ripping.

FIGS. 2 and 3 illustrate steps for manufacturing the coreless paper roll illustrated in FIG. 1.

A toilet paper roll (i.e. paper roll 1) is manufactured by winding up paper, obtained from a parent roll or the like, in a coreless state by using a predetermined manufacturing apparatus (not illustrated). In this case, the paper 2 is wound up into a roll by using water or an adhesive or the like with extremely low adhesive strength, where necessary, or preferably, without using water or an adhesive or the like. The paper roll 1 formed here has no sections with sufficient rigidity since it is simply formed by winding up the paper 2. Thus, the paper roll 1 or the center hole 3 may deform easily, and may thus easily lose its shape.

The paper roll 1 in this state is set in, for example, the predetermined manufacturing apparatus (not illustrated), and a tubular adhesive spraying unit 10 provided in the manufacturing apparatus and having sealed tips is inserted into the center hole 3 of the paper roll 1, as illustrated in FIG. 2.

The adhesive spraying unit 10 is configured such that an insertion end 10 a and an insertion end 10 b are respectively inserted from opposite ends at the peripheral walls of the paper roll 1, namely, opposite ends of the center hole 3, and includes a mechanism (not illustrated) for moving these insertion ends 10 a and 10 b.

The insertion ends 10 a and 10 b are disposed facing each other. The insertion ends 10 a and 10 b each have a tubular shape with a sealed tip and each have a plurality of ejection holes extending to the surface thereof from its inner tube hole. Specifically, the adhesive spraying unit 10 is configured to eject, an adhesive or the like, which is sent into the inner tube holes of the tubular adhesive spraying unit 10 by sending means, such as a pump, provided in the manufacturing apparatus (not illustrated), to the surface of the insertion end 10 a or the like (from the ejection holes).

The insertion ends 10 a and 10 b have a length similar to that of, for example, tiltable support members used for supporting and fixing the paper roll 1 and provided in a common one-touch holder.

In other words, the insertion ends 10 a and 10 b have a length such that, when the paper roll 1 is fitted to the one-touch holder or the like, an adhesive or the like can be ejected to the areas with which the support members of the one-touch holder inserted into the center hole 3 come into contact, and are configured to not allow the adhesive or the like to adhere to the middle area of the center hole 3 in the extending direction thereof, such as the area near the center along the roll axis (i.e. in the width direction of the paper 2) of the paper roll 1.

With regard to the paper roll 1 set at a predetermined position of the aforementioned manufacturing apparatus, the insertion end 10 a of the adhesive spraying unit 10 is inserted from the hole end 3 a side of the center hole 3, and the insertion end 10 b of the adhesive spraying unit 10 is inserted from the hole end 3 b side of the center hole 3.

For example, the insertion ends 10 a and 10 b inserted into the center hole 3 are inserted to positions similar to those of the support members of the one-touch holder (i.e. deep in the center hole 3), as described above, and eject the adhesive or the like. When the adhesive or the like is to be ejected to the inner wall of the center hole 3, the adhered amount of the adhesive may be large at the hole ends 3 a and 3 b and may gradually decrease toward the deep area (i.e. the middle) of the center hole 3, so that the adhesive strength is at the maximum at the opening ends of the hole ends 3 a and 3 b and decreases toward the middle of the center hole 3 to eventually become null.

The adhered amount of the adhesive or the like may be adjusted in this manner so that the wound paper 2 becomes the hardest near the hole ends 3 a and 3 b, the middle section of the paper roll 1 or the paper 2 in the width direction is prevented from being hardened by the adhesive or the like, and a hardened section that facilitates peeling of the paper 2 is also formed in the wound section near the center hole 3.

After the adhesive or the like is sprayed onto the predetermined positions of the center hole 3, the insertion ends 10 a and 10 b are removed from the center hole 3, and a heating unit 11 provided in the manufacturing apparatus (not illustrated) is inserted into the hole ends 3 a and 3 b, as illustrated in FIG. 3.

The heating unit 11 includes, for example, a heating element therein and has heating ends 11 a and 11 b with tapered tips. The heating ends 11 a and 11 b are disposed facing each other and are similar to the insertion end 10 a and the insertion end 10 b described above in that they include a mechanism (not illustrated) for enabling insertion to and removal from the center hole 3. The heating ends 11 a and 11 b have a length substantially similar to that of the insertion ends 10 a and 10 b described above, and have, for example, a shape and size such as not to directly come into contact with the areas to which the adhesive or the like is adhered by the insertion ends 10 a and 10 b.

After the adhesive or the like is adhered to the predetermined positions of the center hole 3 by the adhesive spraying unit 10, for example, the heating unit 11 is immediately inserted into the center hole 3 and the adhesive or the like adhered to the predetermined positions of the center hole 3 penetrates into the paper fibers. Accordingly, the aforementioned areas are quickly dried and predetermined areas are hardened so that the adhesive or the like does not spread more than necessary along the wound peripheral surface and does not spread to a large number of wound layers. The areas to be hardened are, for example, areas of the inner wall surface near the hole ends 3 a and 3 b at the lateral sides of the paper roll 1, such that adequate rigidity for maintaining the roll shape (such as the rigidity in the axial direction of the roll and the rigidity or the like for maintaining the hole diameter of the center hole 3) is produced and that the paper roll 1 can be readily rotated without deforming when the paper roll 1 is set in the one-touch holder.

Because the heating ends 11 a and 11 b are tapered, as described above, when the heating ends 11 a and 11 b are inserted into the center hole 3, the heating ends 11 a and 11 b are disposed closest to the center hole 3 near the opening ends of the hole ends 3 a and 3 b and distant from the center hole 3 in the middle thereof. Therefore, the heating and drying process performed near the opening ends of the hole ends 3 a and 3 b is intense, whereas the heating and drying process performed in the middle of the center hole 3 is relatively moderate. The heating temperature and the drying period or the like are adjusted and controlled so that burning caused by the heating ends 11 a and 11 b coming into contact with the center hole 3 or the paper roll 1 is prevented from occurring. Furthermore, for example, as described above, when the adhered amount of the adhesive or the like is at the maximum at the hole ends 3 a and 3 b of the center hole 3 and gradually decreases toward the middle, the heating operation of the heating unit 11 may be particularly controlled such that the heating and drying process is performed most intensely at the opening ends of the hole ends 3 a and 3 b and the intensity of the heating and drying process is reduced toward the middle of the center hole 3. By drying and hardening only the predetermined positions of the center hole 3 by using the heating unit 11 in this manner, the paper roll 1 is given enough rigidity for preventing it from losing its shape or the like.

Second Embodiment

FIGS. 4 and 5 illustrate steps for manufacturing coreless paper roll by using a coreless paper roll manufacturing method according to a second embodiment of the present invention. Paper roll 1 a according to the second embodiment is coreless toilet paper having a narrow hole (not illustrated) as a center hole and is manufactured so as to be settable in, for example, a holder equipped with a dedicated narrow core. The paper roll 1 a is similar to the above-described paper roll 1 in being not provided with a core, such as paperboard, and is obtained by winding up paper 2 by using water or an adhesive or the like with extremely low adhesive strength, where necessary, or preferably, without using water or an adhesive or the like in the narrow center hole. The paper roll 1 a described above is set in a predetermined manufacturing apparatus (not illustrated), and an adhesive spraying unit 20 provided in the manufacturing apparatus is inserted into the narrow hole (i.e. center hole) of the paper roll 1 a, as illustrated in FIG. 4.

Similar to the adhesive spraying unit 10 described above, the adhesive spraying unit 20 has a tubular shape with sealed tips and is configured such that an insertion end 20 a and an insertion end 20 b are respectively inserted from opposite ends at the peripheral walls of the paper roll 1 a, namely, opposite ends of the narrow center hole, and includes a mechanism (not illustrated) for moving these insertion ends 20 a and 20 b.

The adhesive spraying unit 20 has a plurality of ejection holes extending to the surfaces of the insertion ends 20 a and 20 b from the inner tube holes thereof. Specifically, the adhesive spraying unit 20 is configured to eject, for example, an adhesive, which is sent into the inner tube holes of the adhesive spraying unit 20 by sending means, such as a pump, provided in the manufacturing apparatus (not illustrated), to the surface of, for example, the insertion end 20 a (from the ejection holes).

The insertion ends 20 a and 20 b have a length similar to that of, for example, tiltable support members used for supporting and fixing the paper roll 1 a and provided in a common one-touch holder.

Furthermore, the insertion ends 20 a and 20 b are configured to increase the inner diameter of the narrow hole of the paper roll 1 a to a predetermined size to form center holes 4 a and 4 b having a circular shape, and to adhere an adhesive to the inner walls of the center holes 4 a and 4 b.

In other words, the insertion ends 20 a and 20 b at least have a length such that, when the paper roll 1 a is fitted to, for example, the one-touch holder, the center holes 4 a and 4 b can be formed with enough depth that allows the support members of the one-touch holder to be insertable therein, and, for example, an adhesive can be ejected to the areas with which the support members of the one-touch holder come into contact.

With regard to the paper roll 1 a set at a predetermined position of the aforementioned manufacturing apparatus, the insertion end 20 a of the adhesive spraying unit 10 is inserted from the center hole 4 a side, and the insertion end 20 b of the adhesive spraying unit 10 is inserted from the center hole 4 b side.

For example, the insertion ends 10 a and 10 b respectively inserted into the center holes 4 a and 4 b are inserted to positions similar to those of the support members of the one-touch holder, as described above, and eject the adhesive or the like.

When the adhesive or the like is to be ejected into the center holes 4 a and 4 b, the adhered amount of the adhesive or the like may be large at the lateral ends (i.e. the openings of the center holes 4 a and 4 b) of the paper roll 1 a and may gradually decrease toward the deep areas of the center holes 4 a and 4 b (i.e. the middle of the paper roll 1), so that the adhesive strength decreases toward the deep areas of the center holes 4 a and 4 b to eventually become null.

The adhered amount of the adhesive or the like may be adjusted in this manner so that the wound paper 2 becomes the hardest near the lateral ends of the paper roll 1 a, the middle section of the paper roll 1 a in the width direction is prevented from being hardened by the adhesive or the like, and a hardened section that facilitates peeling of the paper 2 is also formed near the terminal ends (i.e. the center holes 4 a and 4 b) of the paper roll 1 a.

After the adhesive, for example, is sprayed onto the predetermined positions of the center holes 4 a and 4 b, the insertion ends 20 a and 20 b are respectively removed from the center holes 4 a and 4 b, and a heating unit 21 provided in the manufacturing apparatus (not illustrated) is inserted into the center holes 4 a and 4 b, as illustrated in FIG. 5.

Similar to the heating unit 11, the heating unit 21 includes, for example, a heating element therein and has heating ends 21 a and 21 b with tapered tips. The heating ends 21 a and 21 b are disposed facing each other and include a mechanism (not illustrated) for enabling insertion to and removal from the center holes 4 a and 4 b, respectively. The heating ends 21 a and 21 b have a length substantially similar to that of the insertion ends 20 a and 20 b described above, and have, for example, a shape and size such as not to directly come into contact with the areas to which the adhesive or the like is adhered by the insertion ends 20 a and 20 b.

After the adhesive or the like is adhered to the predetermined positions of the center holes 4 a and 4 b by the adhesive spraying unit 20, for example, the heating unit 21 is immediately inserted into the center holes 4 a and 4 b, and the adhesive or the like adhered to the predetermined positions of the center holes 4 a and 4 b penetrates into the paper fibers. Accordingly, the aforementioned areas are quickly dried and predetermined areas are hardened so that, for example, the adhesive does not spread more than necessary along the wound peripheral surface and does not spread to a large number of wound layers. The areas to be hardened are, for example, areas of the inner wall surfaces of the center holes 4 a and 4 b at the lateral sides of the paper roll 1 a, such that adequate rigidity for maintaining the roll shape (such as the rigidity in the axial direction of the roll and the rigidity for maintaining the hole diameter of the center holes 4 a and 4 b) is produced and that the paper roll 1 a can be readily rotated without deforming when the paper roll 1 a is set in the one-touch holder.

Because the heating ends 21 a and 21 b are tapered, as described above, when the heating ends 21 a and 21 b are inserted into the respective center holes 4 a and 4 b, the heating ends 21 a and 21 b are disposed closest to the center holes 4 a and 4 b near the opening ends thereof and distant from the center holes 4 a and 4 b at the deep areas thereof. Therefore, the heating and drying process performed near the opening ends of the center holes 4 a and 4 b is intense, whereas the heating and drying process performed in the deep areas of the center holes 4 a and 4 b is relatively moderate. The heating temperature, the drying period and the like are adjusted and controlled so that burning caused by the heating ends 21 a and 21 b coming into contact with the center holes 4 a and 4 b or the paper roll 1 a is prevented from occurring. Furthermore, for example, as described above, when the adhered amount of the adhesive or the like is at the maximum at the opening ends of the center holes 4 a and 4 b and gradually decreases toward the middle of the paper roll 1 a or the paper 2 in the width direction, the heating operation of the heating unit 21 may be particularly controlled such that the heating and drying process is performed most intensely at the opening ends of the center holes 4 a and 4 b and the intensity of the heating and drying process is reduced toward the deep areas of the center holes 4 a and 4 b (i.e. toward the middle).

By drying and hardening the center holes 4 a and 4 b by using the heating unit 21 in this manner, the paper roll 1 a is given enough rigidity for preventing it from losing its shape.

When the coreless paper roll 1 or 1 a is to be manufactured in this manner, the opening ends of the center hole or holes formed in the center of the roll are hardened the most, and the adhesive strength is reduced or eliminated in the middle section of the paper 2 in the width direction, so that the paper 2 can be peeled and used even in the central section of the roll (i.e. the section of the paper 2 to be completely used up).

REFERENCE SIGNS LIST

1, 1 a paper roll

2 paper

3, 4 a, 4 b center hole

3 a, 3 b hole end

10, 20 adhesive spraying unit

10 a, 10 b, 20 a, 20 b insertion end

11, 21 heating unit

11 a, 11 b, 21 a, 21 b heating end 

1. A paper roll manufacturing method comprising: a first step for winding up paper to form paper roll having a roll shape; a second step for inserting an insertion section, which ejects an adhesive, into a center hole of the paper roll; a third step for causing the adhesive to adhere to a predetermined position of the center hole; and a fourth step for performing a heating and drying process on an area to which the adhesive is adhered so as to harden opposite ends of the center hole, wherein the third step includes causing the adhesive to adhere to near opposite extending ends of the center hole, the adhesive having adhesive strength to an extent that the paper wound up into the roll shape is peelable when the paper roll is to be used, and wherein the fourth step includes drying the adhesive adhered to the center hole before the adhesive spreads from the predetermined position of the center hole.
 2. The paper roll manufacturing method according to claim 1, wherein the second step includes inserting the insertion section toward a middle of the center hole from the opposite extending ends of the center hole and increasing a hole diameter at the opposite ends of the center hole to a predetermined size, and wherein the third step includes causing the adhesive to adhere to areas of the center hole with the increased hole diameter.
 3. The paper roll manufacturing method according to claim 1, wherein the third step includes decreasing an adhered amount of the adhesive toward a middle of the center hole from the opposite extending ends of the center hole, and wherein the fourth step includes performing heating and drying such that the opposite ends of the center hole are maximally hardened.
 4. The paper roll manufacturing method according to claim 2, wherein the third step includes decreasing an adhered amount of the adhesive toward a middle of the center hole from the opposite extending ends of the center hole, and wherein the fourth step includes performing heating and drying such that the opposite ends of the center hole are maximally hardened. 